(1) Field of the Invention
The present invention relates generally to marine tow cables, and more particularly to a system and method for making marine tow cables capable of sensing the temperature of a water column.
(2) Description of the Prior Art
Sonar performance is enhanced by knowledge of the temperature profile of the water in which the sonar is operating. For example, in towed cable/array applications, it is desirable to measure water temperature along the length of the cable/array. U.S. Pat. No. 6,072,928, discloses a tow cable for measuring temperature in a water column that comprises an optical fiber core, an electrically conducting polymer jacket concentrically superimposed over the cable core and a temperature sensor embedded in the electrically conducting polymer jacket. However, this design may not be rugged enough to withstand winding/unwinding forces experienced by a sonar cable/array.
Accordingly, it is an object of the present invention to provide a system and method for sensing water temperature along the length of a towed cable/array.
Another object of the present invention is to provide a system and method that can be used in conjunction with existing tow cables/arrays for sensing water temperature.
Still another object of the present invention is to provide a system and method of modifying existing tow cables/arrays with a rugged water temperature sensing arrangement that can withstand winding/unwinding forces.
Other objects and advantages of the present invention will become more obvious hereinafter in the specification and drawings.
In accordance with the present invention, a system for sensing water temperature is provided. The system includes a tow cable with an exterior surface having at least one helical groove formed therein along the length thereof. A metal tube lies in each helical groove. At least one optical temperature sensing element is provided in each metal tube. A thermally-conducting material fills each metal tube and surrounds each optical temperature sensing element contained therein. An outer jacket layer having a smooth outer surface is formed over the tow cable and metal tube.